Fix deprecated function CRM_Core_OptionGroup::getValue, use CRM_Core_PseudoConstant::getKey

Issue

In recent CiviCRM versions, this line:

$completed_status_id = CRM_Core_OptionGroup::getValue('contribution_status', 'completed', 'name');

is generating this warning:

Deprecated function CRM_Core_OptionGroup::getValue, use CRM_Core_PseudoConstant::getKey.

due to this core deprecation warning.

Proposal

Maybe we could replace it with this...?

$completed_status_id = civicrm_api3('OptionValue', 'getsingle', [
  'option_group_id' => 'contribution_status',
  'name' => 'completed',
  'is_active' => 1
])['value'];